1. Field of the Invention
The invention relates to a method for producing a riveted connection between a ball joint pin and a component in the form of a metal sheet. The method includes a first step wherein the ball joint pin is joined into the preliminary hole by a joining tool such that an underside of the plate section of the ball joint pin is flatly supported on the contact section of the sheet metal component. The hollow-cylindrical rivet collar section is in a second step deformed in the direction of the sheet metal component in a controlled fashion by a forming die, particularly by a riveting punch, in order to produce the riveted connection.
2. Description of the Related Art
Ball joint pins are used in various fields for producing hinge joint mechanisms, particularly a hinge point or a hinged suspension. In the automotive sector, for example, these ball joint pins are used for hinge joint mechanisms of tailgates and front hoods.
In order to reduce the production steps, in the series production of products, in particular, in the series production of automobiles, it is also known to use prefabricated subassemblies such as, for example, a prefabricated subassembly comprising a sheet metal component and at least one ball joint pin preinstalled thereon for producing a hinge joint mechanism.
Known ball joint pins comprise at least one ball end section and an adjoining shaft section, wherein dependent on the respective application the shaft section is adjoined by different pin sections, particularly a connecting section for producing a connection with a sheet metal component. For example, the ball joint pin may comprise a cylindrical rivet section that adjoins the shaft section in order to produce a riveted connection with a sheet metal component, wherein the cylindrical rivet section is deformed over part of its circumference by means of wobble riveting in order to produce a riveted connection with a component, particularly in the form of a metal sheet, namely until the rivet section made of solid material is in contact with the metal sheet. Significant deformation forces are required in order to achieve the high deformation degrees necessary for cold-forming the riveting section made of solid material during the wobble riveting process. A riveted connection between a ball joint pin and a metal sheet produced by means of wobble riveting is very strong and suitable for transmitting high forces. However, cracks in the ball joint pin and therefore potential breaking points may be disadvantageously formed due to the high deformation forces required for the riveting process.
A rigid connection between a ball joint pin and a component, preferably a metal sheet, can alternatively also be produced by means of welding. Such an integral connection likewise makes it possible to transmit high forces. However, it is disadvantageous that such welding processes are not suitable for all materials and require elaborate production steps.
Conventional ball joint pins may also comprise a plate section that adjoins the shaft section and is in turn adjoined by a cylindrical connecting section that is made of solid material and comprises an external thread. The ball joint pin is inserted into an installation opening in the component, particularly a metal sheet, with its cylindrical connecting section, namely until the plate section comes in contact with the sheet metal component. Subsequently, a nut element is screwed on the external thread in order to thereby fix the ball joint pin on the sheet metal component. Although such a screw connection is capable of transmitting high forces, its implementation in series production is technically elaborate and therefore uneconomical due to the large number of required installation steps.
The above-described connecting techniques have in common that a separate production step is respectively required after the manufacturing process of the sheet metal component in order to install the ball joint pin on the component, particularly a metal sheet. The resulting high installation effort is disadvantageously associated with high costs. It would therefore be desirable to integrate the production of the riveted connection between the ball joint pin and the component, which is at least sectionally realized in the form of a metal sheet, into the manufacturing process of the sheet metal component in order to thereby eliminate subsequent production steps.
German Patent No. DE 10 2009 037 427 A1 already discloses a method for producing a riveted connection between a functional element and a sheet metal component, in which a hole is punched into the sheet metal component by a hollow-cylindrical rivet section of the functional element while it is supported on a die such that a rivet flange is produced by the die. Prior to the completion of the rivet flange, the functional element is additionally pressed downward such that a region of the hollow-cylindrical rivet section facing the shaft section is deformed into an annular lock seam that abuts on the sheet metal component on the side facing away from the rivet flange and facing the shaft section. As a result, the contact section of the sheet metal component surrounding the punched hole is deformed in such a way that it accommodates the annular lock seam in a nearly flush fashion, i.e. the annular lock seam is sunk in the sheet metal component. Since the annular lock seam is sunk in the sheet metal component, such a riveted connection disadvantageously protrudes farther from the underside of the sheet metal component and weakens the sheet metal component in the connecting region.
Based on the above-described background art, the technical problem to be solved is to provide a method for producing a riveted connection between a ball joint pin and a component in the form of a metal sheet, as well as a corresponding prefabricated subassembly consisting of a ball joint pin and a component in the form of a metal sheet, which respectively eliminates the above-described disadvantages and, in particular, allows a simple, fast and cost-efficient manufacture of prefabricated subassemblies comprising the sheet metal component and the already preinstalled ball joint pin in one manufacturing process. This problem is respectively solved with a method for producing a riveted connection between a ball joint pin and a component in the form of a metal sheet.